Power tools that use a battery as a power supply typically comprise a controller having a control (circuit) board equipped with a microcontroller, etc. for controlling the drive (output) of a motor, as disclosed e.g., in Japanese Laid-open Patent Publication 2013-226617. The controller is housed in a battery-mount part formed at an end part of the tool housing and is cooled by outside air (motor cooling air) drawn (sucked) in through air-suction ports provided in side surfaces of the battery-mount part.